1. Field of the Invention
The present invention relates to a zipper containment system and more particularly to a zipper containment system for use on an encasement for a mattress to prevent the egress of bed bugs, parasites, dust mites and allergens from a zipper that is in a closed position.
2. Description of the Prior Art
Encasements are known to be used as a prophylactic cover over a mattress or box spring to provide protection from various situations, such as parasites, dust mites, allergens and stains, for example, pet stains and stains from incontinent children and adults. As used herein, the term encasement refers to mattress encasements and box spring encasements individually and collectively. Examples of such encasements are disclosed in US patent application Publication Nos.: US 2012/0260426; US 2012/0255120; 2012/0192356; 2012/0167302; and 2011/00100856 as well as U.S. Pat. Nos. 8,087,111 and 8,156,588, all hereinafter incorporated by reference.
Such encasements are known to have an opening along one or more sides to enable the encasements to be installed over a mattress or box spring. A zipper is used to close the opening. Unfortunately, even when the zipper is fully closed or zipped up, a small gap exists between the zipper slide and the zipper stop. This gap is normally of sufficient size to allow for the egress of parasites, dust mites and allergens.
In order to prevent the egress of such parasites, dust mites and allergens in encasements, various containment techniques have been developed. For example, US Patent Application No. US 2013/0326820 A1 discloses an encasement, which includes a zipper for enabling a mattress or box spring to be sapped into said encasement. In order to prevent parasites, dust mites and allergens from egressing through zipper opening, a foam pad is stitched to the underside of the encasement adjacent the zipper stop so as to cover a portion of the zipper, the zipper slide and the gap.
There are several problems with the technique discussed above. For example, extra materials and labor are required thus making the encasement relatively expensive to manufacture. In addition, this device relies on a relatively snug fit between the encasement and the mattress so that the mattress compresses the foam against the encasement to seal the gap. As such, the efficacy of the device depends on the relative fit between the encasement and the mattress. Unfortunately, encasements come in all different sizes. If the encasement does not provide a snug fit and compress the foam, the device will be ineffective in preventing the egress of parasites, dust mites and allergens.
In order to solve this problem, other techniques have been developed which eliminate the need for a foam pad and the problems associated with it. For example, U.S. Pat. No. 8,087,111, discloses the use of a flap for covering the zipper slide, the zipper stop and a portion of the zipper. The flap does not provide a positive seal against the zipper tape. As such, even with the flap in a closed position, an exit path exists along the zipper tape allowing parasites and dust mites to escape from the encasement.
U.S. Pat. No. 2,400,731 discloses a mattress encasement, which includes a flap that covers the zipper as well as the zipper slide, zipper stops and the gap. The flap merely covers the gap but does not seal against it. As such, this device allows the egress of parasites, allergens, and dust mites, both into and out of the gap.
Another problem with the devices discussed above is that the containment systems discussed above is that they are currently available only as original equipment devices. Thus, manufacturers must make two different types of encasements; one with a containment system and one without a containment system. As such, these encasements are more expensive to manufacture because of the additional manufacturing process steps to include a parasite proof allergen encasement. Moreover, consumers that own a mattress encasement without a parasite, allergen, and dust mite proof zipper enclosure then must purchase a new encasement with such zipper enclosure protection in order to add parasite protection, which is an added expense for the consumer.
Thus, there is a need for an encasement that can provide a positive compression seal of the gap between the zipper slide and the zipper stop independent of the fit between the mattress and the encasement, as well as a containment system that can be installed as an aftermarket device on an existing encasement to add protection from the egress of parasites, dust mites and allergens.